I want 55 5th St. But, noooo!

January 2, 2008 5:24 PM

How are house numbers allotted in Walton County, FL? The fellow at the courthouse said it is determined by distance and has something to do with emergency services. The house right next door to me is 53, but my number is 61. Why isn't it 55? Googling has failed me.
posted by wsg to home & garden (11 comments total)

If it's based on distance, you're probably 8 distance-units - yards would be my guess - away from your neighbor based on some criteria. That kind of numbering means that emergency vehicles can find you just by driving up the street for 61 yards (or whatever units it is) instead of trying to read tiny dim house numbers.
posted by Tomorrowful at 5:27 PM on January 2

Essentially, in most American locales, every 100 house number "units" equals some defined distance - maybe an eighth of a mile. Within those 100-unit measures, there may be 21 houses - eleven on one side of the street and ten on the other. The house may not be equidistant from one another. If one house is 63% of the way from the start point of those hundred units and on the "even" side of the street, it will get the number 62 or 64. If your house number is 53 and your neighbor's number is 61, assume that he's roughly 8% of the unit distance further from the start than you. This way, all the "same" numbers on different (say, 64 West) will line up in a straight line. Ideally, at least. So in Chicago, 800 North (no matter what street you're on) means you're one mile north of the start street.
posted by Dee Xtrovert at 5:33 PM on January 2

In my experience, it's quite rare that street numbering uses up every number in sequence. They have to allow for the possibility that someone will tear down these buildings and put up more than are currently there.
posted by winston at 5:37 PM on January 2

Here in Portland, each 100 house-number counts is one block. The location of the lot in the block determines its house numbers.

In older cities (e.g. Salem Mass, where I used to live) they just numbered them sequentially. That's how they did it in the early 1800's and before. But later it became clear that was a recipe for problems, because sometimes redevelopment would take a lot which had a single house on it, and convert it to a large number of dwellings by subdividing. And there weren't any numbers left for them all.

So newer cities, and newer parts of older cities, started using a coordinate-based assignment scheme which was deliberately sparse.

That had the additional advantage of making it easier to locate a house based on its address, since the street it was on was one coordinate, and the house number effectively was the other coordinate on a regular grid.
posted by Steven C. Den Beste at 5:38 PM on January 2

Fwiw, I've seen decameters used in Puerto Rico. My parents in Georgia (U.S.) live on a highway, 18 miles from some major starting point, and their number is 19 thousand NNN. This is more common than you think.
posted by cmiller at 6:42 PM on January 2

All of this is well and good, but be aware that in some locales you can petition for a variance from whatever government agency hands out address numbers.
posted by rhizome at 7:05 PM on January 2

About ten years ago they changed all the street numbers in Vermont to comply with EMS/911 requirements. The houses are now numbered based on their distance in meters from where the road begins or from where the town line begins. So here in Vermont it's conceivable that you can have two houses with the same number on the same road because they are in different townships.

My sense is that you have a similar numbering system in Florida.
posted by Xurando at 7:19 PM on January 2

meters? not yards or feet?

Interesting. The metric system subtly strikes the US again!
posted by niles at 7:41 PM on January 2

It doesn't look like Vermont mandated how the roads were re-addressed, just that the addresses were locatable. Some towns used 5.28' feet (1/1000 of a mile), others used 25' or 50'. I guess some wacky ones used meters, but it was a local choice.
posted by smackfu at 9:20 PM on January 2

Have you seen this previous AskMeFi post on house numbering in the US? It lays out some elements of the debate, though I can't remember if it ever resolved the question or not.
posted by librarylis at 11:19 PM on January 2

So in Chicago, 800 North (no matter what street you're on) means you're one mile north of the start street.

This is basically the crux of it, and as you alluded to, the emergency services angle is the reason why. Generally, there's a very well defined point in the town where the address numbers start at zero (or 100 or whatever), and then increase out from that point. Knowing that point in combination with the address number of where they're going allows emergency responders to basically know where they're headed without having to check a map for what block they're supposed to be on. In towns that I've lived in, the address numbers are generally spread out so that the numbers go up by 100 every block. So, as an example, if Main Street is the address start point, and your place was at 793 on a street perpendicular to Main, the fire department would automatically know that it would have to go almost eight blocks north of Main to get to your house. It's a lot easier to count blocks that you pass instead of constantly searching for address numbers, especially so at night.
posted by LionIndex at 11:49 AM on January 4